This invention relates to improved equipment and methods for making continuous fastener products and the like, and to products produced by the equipment and methods.
Fastener products, such as hook components of hook-and-loop fasteners, are manufactured by a continuous molding method employing a cylindrical mold roll which has fastener-shaped cavities formed in its periphery. Often the mold roll is formed of an axially compressed stack of ring-form mold plates. In operation, molten polymer from an extruder is introduced into a pressure zone in which the molten polymer is forced under high pressure into the fastener cavities of the cooled mold roll, to form fastener elements (e.g. hooks) integrally molded with a base layer. In some cases the pressure zone is a nip formed by a mold roll and an adjacent pressure roll. In other configurations the pressure zone is formed between a conforming stationary pressure head and a mold roll. Typically, the smaller the fastener elements (or the like), the faster the optimal production speed. The more viscous the resin, or the lower the temperature of the cooled roll, the higher must be the pressure achieved in the pressure zone in order to make a satisfactory product. Typically, mold rolls of about 10 inch diameter and 12 inches in axial length have been employed.